The present invention generally relates to a resonance apparatus and more particularly, to a dielectric resonator which is integrally incorporated into a dielectric base plate on which an electronic circuit is formed.
As shown in FIG. 1, one conventional filter employing a dielectric resonator therein has been so constructed as to accommodate a dielectric resonator 4 of a columnar or cylindrical shape or the like within a metallic case 2, with the dielectric resonator 4 being supported by a support member 6 of an insulating material. In some cases, the metallic case 2 has been so designed as to internally accommodate an electronic circuit, for example, an MIC (Microwave Integrated Circuit) and such being the case, the dielectric resonator 4 is placed on a dielectric base plate 8 which is provided for the MIC, the base-plate 8 supporting the supporting member 6, and the base plate 8 also being connected with a microstrip line 10 communicating with the MIC and with proper positional relationship therebetween. There are illustrated in FIG. 1, magnetic lines M of force in the case where a resonance mode of the dielectric resonator 4 is the TE mode.
As stated above, when the dielectric resonator 4 is used in this way connected with an MIC or the like, the filter portion where the dielectric resonator 4 is located, is elevated extremely high as compared with the other circuit components, which causes the drawback that a large space is necessarily required. In addition, there has been also the drawback that a whole electronic circuit including the aforementioned dielectric resonator 4 therein must be manufactured at a high cost owing to the fact that the dielectric resonator 4 differs from the dielectric base plate 8 in material.